Optical filter

Abstract

The present invention relates to an optical filter comprising a substrate and a dielectric multilayer film that is laminated, as an outermost layer, on at least one principal surface side of the substrate, the substrate having a resin film having a thickness of 3 µm or less and including a resin, a UV pigment 1 that has a maximum absorption wavelength of 360-390 nm in the resin, and an IR pigment that has a maximum absorption wavelength of 680-800 nm in the resin, and the optical filter satisfying all of prescribed spectral characteristics (i-1)-(i-8).

Description

[Technical Field]

[0001] The present invention relates to an optical filter that transmits light in the visible wavelength region and blocks light in the ultraviolet wavelength region and the near-infrared wavelength region. [Background technology]

[0002] In imaging devices using solid-state image sensors, optical filters are used that transmit visible light (hereinafter also referred to as "visible light") and block light in the ultraviolet wavelength range (hereinafter also referred to as "ultraviolet light") and near-infrared wavelength range (hereinafter also referred to as "near-infrared light") in order to reproduce colors well and obtain sharp images.

[0003] As an optical filter, for example, a reflective filter is known that uses the interference of light from a dielectric multilayer film, which is made by alternately stacking dielectric thin films with different refractive indices on one or both sides of a transparent substrate, to reflect the light that needs to be blocked. However, because the optical thickness of the dielectric multilayer film changes depending on the angle of incidence of light, such an optical filter may experience light leakage, where near-ultraviolet light, which should have high reflectivity, is transmitted when incident at a high angle of incidence. Since image sensors are also sensitive to the near-ultraviolet light region, if the shielding of near-ultraviolet light is insufficient, there is a risk that the acquired visible light image may exhibit image quality degradation caused by unwanted light, such as flare or ghosting. Thus, there is a need for near-infrared and ultraviolet light cut-off filters that prevent the spectral sensitivity of solid-state image sensors from being affected by the angle of incidence.

[0004] Here, Patent Documents 1 and 2 describe optical filters that combine near-ultraviolet light blocking ability and near-infrared light blocking ability by combining an absorption layer containing near-ultraviolet light absorbing dyes and near-infrared light absorbing dyes in a transparent resin with a dielectric multilayer film. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent No. 6020746 [Patent Document 2] Japanese Patent No. 6773161 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, while the optical filters described in Patent Documents 1 and 2 take into account the ability to block near-ultraviolet light up to an incident angle of 30 degrees, there was room for improvement in terms of blocking performance at even higher incident angles.

[0007] The present invention aims to provide an optical filter that has high transmittance of visible light and high shielding of near-infrared and ultraviolet light, and in particular suppresses flare and ghosting by suppressing the decrease in shielding performance of ultraviolet light at high incidence angles. [Means for solving the problem]

[0008] The present invention provides an optical filter having the following configuration. [1] An optical filter comprising a substrate and a dielectric multilayer film laminated as the outermost layer on at least one main surface side of the substrate, The substrate comprises a resin, a UV dye 1 having a maximum absorption wavelength of 360-390 nm in the resin, and an IR dye having a maximum absorption wavelength of 680-800 nm in the resin, and has a resin film with a thickness of 3 μm or less. The optical filter is an optical filter that satisfies all of the following spectral characteristics (i-1) to (i-8). (i-1) Average transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm and an incident angle of 0 degrees 360-400(0)AVE less than 0.5% (i-2) Average transmittance T in the spectral transmittance curve at wavelengths of 350-390 nm and an incident angle of 50 degrees 350-390(50)AVE less than 0.5% (i-3) Average transmittance T in the spectral transmittance curve at wavelengths of 400-430 nm and an incident angle of 0 degrees 400-430(0)AVE over 35% (i-4) Average transmittance T in the spectral transmittance curve at wavelengths of 430-500 nm and an incident angle of 0 degrees 430-500(0)AVE over 88% (i-5) In the spectral transmittance curve with a wavelength of 350 to 450 nm and an incident angle of 0 degrees, the wavelength UV50 at which the transmittance is 50% (0) is between 400 and 430 nm (i-6) In the spectral transmittance curve with a wavelength of 350 to 450 nm and an incident angle of 0 degrees, the wavelength UV10 when the transmittance is 10% (0) and the wavelength UV70 when the transmittance is 70% (0) The absolute value of the difference between them is defined as ΔUV 70-10(0) and In the spectral transmittance curve with a wavelength of 350 to 450 nm and an incident angle of 30 degrees, the wavelength UV10 when the transmittance is 10% (30) and the wavelength UV70 when the transmittance is 70% (30) The absolute value of the difference between them is defined as ΔUV 70-10(30) When it is defined as such, ΔUV 70-10(0) and ΔUV 70-10(30) The absolute value of the difference between them is 2.5 nm or less (i-7) In the spectral transmittance curve with a wavelength of 600 to 700 nm and an incident angle of 0 degrees, the wavelength IR50 at which the transmittance is 50% (0) is between 610 and 670 nm, and in the spectral transmittance curve with a wavelength of 600 to 700 nm and an incident angle of 30 degrees, the wavelength IR50 at which the transmittance is 50% (30) is between 610 and 670 nm (i-8) The wavelength IR50 (0) and the wavelength IR50 (30) The absolute value of the difference between them is 5 nm or less

Advantages of the Invention

[0009] According to the present invention, an optical filter having high transmittance of visible light and high shielding properties of near-infrared light and ultraviolet light, and suppressing flare and ghost by suppressing a decrease in the shielding property of ultraviolet light at a high incident angle can be provided.

Brief Description of the Drawings

[0010] [Figure 1] FIG. 1 is a cross-sectional view schematically showing an example of an optical filter according to an embodiment. [Figure 2]Figure 2 is a schematic cross-sectional view showing another example of an optical filter according to one embodiment. [Figure 3] Figure 3 is a schematic cross-sectional view showing another example of an optical filter according to one embodiment. [Figure 4] Figure 4 is a schematic cross-sectional view showing another example of an optical filter according to one embodiment. [Figure 5] Figure 5 shows the spectral internal transmittance curve of the resin film in Example 2-19. [Figure 6] Figure 6 shows the spectral internal transmittance curve of the resin film in Example 2-1. [Figure 7] Figure 7 shows the spectral internal transmittance curve of the resin film in Example 2-8. [Figure 8] Figure 8 shows the spectral transmittance curve of the optical filter in Example 3-18. [Figure 9] Figure 9 shows the spectral transmittance curve of the optical filter in Example 3-1. [Figure 10] Figure 10 shows the spectral transmittance curve of the optical filter in Example 3-6. [Modes for carrying out the invention]

[0011] Embodiments of the present invention will be described below. In this specification, near-infrared absorbing dyes may be abbreviated as "NIR dyes," and ultraviolet absorbing dyes may be abbreviated as "UV dyes." In this specification, the compound represented by formula (I) is referred to as compound (I). The same applies to compounds represented by other formulas. A dye consisting of compound (I) is also referred to as dye (I), and the same applies to other dyes. Furthermore, the group represented by formula (I) is also referred to as group (I), and the same applies to groups represented by other formulas.

[0012] In this specification, internal transmittance is defined by the formula {measured transmittance / (100-reflectance)}×100, which is the transmittance obtained by subtracting the effect of interfacial reflection from the measured transmittance. In this specification, absorbance is -log 10 It is calculated from the (internal) transmittance using the formula ((internal) transmittance / 100). In this specification, the spectral transmission of a substrate and the transmission when a dye is contained in a resin all refer to "internal transmission," even when the term "transmission" is used. On the other hand, the transmission measured by dissolving the dye in a solvent such as dichloromethane, the transmission of a dielectric multilayer film, and the transmission of an optical filter having a dielectric multilayer film are measured transmissions.

[0013] In this specification, for a particular wavelength range, a transmittance of, for example, 90% or more means that the transmittance does not fall below 90% across the entire wavelength range, i.e., the minimum transmittance in that wavelength range is 90% or more. Similarly, for a particular wavelength range, a transmittance of, for example, 1% or less means that the transmittance does not exceed 1% across the entire wavelength range, i.e., the maximum transmittance in that wavelength range is 1% or less. The same applies to internal transmittance. The average transmittance and average internal transmittance in a particular wavelength range are the arithmetic mean of the transmittance and internal transmittance for every 1 nm in that wavelength range. Spectral characteristics can be measured using an ultraviolet-visible-near-infrared spectrophotometer. In this specification, the symbol "~" used to indicate a numerical range includes both upper and lower limits.

[0014] <Optical filters> An optical filter according to one embodiment of the present invention (hereinafter also referred to as "this filter") comprises a substrate and a dielectric multilayer film laminated as the outermost layer on at least one main surface side of the substrate, and is an optical filter that satisfies specific spectral characteristics described later. Here, the substrate has a resin film containing a resin, a UV dye 1 having a maximum absorption wavelength of 360 to 390 nm in the resin, and an IR dye having a maximum absorption wavelength of 680 to 800 nm in the resin, with a thickness of 3 μm or less. The reflective properties of the dielectric multilayer film and the absorption properties of the dyes in the resin film enable the overall optical filter to achieve excellent transmittance in the visible light region and excellent shielding in the near-ultraviolet and near-infrared light regions. In particular, by including ultraviolet-absorbing dyes or near-infrared-absorbing dyes in the substrate, changes in the spectral characteristics of the dielectric multilayer film at high incidence angles, such as light loss in the ultraviolet and near-infrared regions, can be suppressed by the absorption properties of the substrate. Each dye and resin will be described later.

[0015] An example of the configuration of this filter will be explained using the drawings. Figures 1 to 4 are schematic cross-sectional views showing an example of an optical filter according to one embodiment. The optical filter 1A shown in Figure 1 is an example in which a dielectric multilayer film 30 is provided on one main surface side of the substrate 10. Note that "having a specific layer on the main surface side of the substrate" is not limited to cases where the layer is in contact with the main surface of the substrate, but also includes cases where another functional layer is provided between the substrate and the layer.

[0016] The optical filter 1B shown in Figure 2 is an example in which a dielectric multilayer film 30 is present on both main surfaces of the substrate 10.

[0017] The optical filter 1C shown in Figure 3 is an example in which the substrate 10 has a support 11 and a resin film 12 laminated on one main surface side of the support 11. The optical filter 1C further has dielectric multilayer films 30 on top of the resin film 12 and on the main surface side of the support 11 where the resin film 12 is not laminated.

[0018] The optical filter 1D shown in Figure 4 is an example in which the substrate 10 has a support 11 and a resin film 12 laminated on both main surfaces of the support 11. The optical filter 1D further has a dielectric multilayer film 30 on each of the resin films 12.

[0019] The optical filter of the present invention satisfies all of the following spectral characteristics (i-1) to (i-8). (i-1) Average transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm and an incident angle of 0 degrees 360-400(0)AVE less than 0.5% (i-2) Average transmittance T in the spectral transmittance curve at wavelengths of 350-390 nm and an incident angle of 50 degrees 350-390(50)AVE less than 0.5% (i-3) Average transmittance T in the spectral transmittance curve at wavelengths of 400-430 nm and an incident angle of 0 degrees 400-430(0)AVE over 35% (i-4) Average transmittance T in the spectral transmittance curve at wavelengths of 430-500 nm and an incident angle of 0 degrees 430-500(0)AVE over 88% (i-5) In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 0 degrees, the wavelength at which the transmittance is 50% is UV50 (0) It is located at 400-430nm. (i-6) In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 0 degrees, when the transmittance is 10% at the wavelength UV10 (0) And, when the transmittance is 70%, the wavelength is UV70 (0) The absolute value of the difference between the two is ΔUV 70-10(0) year, In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 30 degrees, the wavelength UV10 when the transmittance is 10% (30) And, when the transmittance is 70%, the wavelength is UV70 (30) The absolute value of the difference between the two is ΔUV 70-10(30) In that case, ΔUV 70-10(0) and ΔUV 70-10(30) The absolute value of the difference is 2.5 nm or less. (i-7) In the spectral transmittance curve for wavelengths of 600-700 nm and an incident angle of 0 degrees, the wavelength at which the transmittance is 50% is IR50. (0) The wavelength IR50 is located at 610-670 nm, and in the spectral transmittance curve at wavelengths of 600-700 nm and an incident angle of 30 degrees, the transmittance is 50%. (30) It is located at 610-670nm. (i-8) The aforementioned wavelength IR50 (0) and wavelength IR50 (30) The absolute value of the difference is 5 nm or less.

[0020] This filter, which satisfies all spectral characteristics (i-1) to (i-8), is an optical filter that maintains good transmittance of visible light, particularly blue light, as shown in characteristics (i-3) to (i-4), while suppressing the decrease in ultraviolet light shielding performance at high incidence angles, as shown in characteristics (i-1) to (i-2).

[0021] Satisfying spectral characteristics (i-1) means that the material has high light-shielding properties in the ultraviolet light region with wavelengths of 360-400 nm. 360-400(0)AVE Preferably, it is 0.4% or less. To satisfy the spectral characteristics (i-1), for example, one can use a dye with high absorption capacity in the near-ultraviolet region.

[0022] Satisfying spectral characteristics (i-2) means that, in the ultraviolet light region of 350-390 nm wavelength, light leakage is less likely even at high incident angles, resulting in high light-shielding properties. 350-390(50)AVE Preferably, it is 0.4% or less. To satisfy the spectral characteristics (i-2), for example, one can use a dye with high absorption capacity in the near-ultraviolet region.

[0023] Satisfying spectral characteristics (i-3) means that the material exhibits excellent transmittance of blue light before the UV absorption onset band at wavelengths of 400-430 nm. 400-430(0)AVE The percentage is preferably 37% or more, and more preferably 38% or more. To satisfy the spectral characteristics (i-3), for example, UV dyes with excellent steepness or IR dyes with high blue band transmittance can be used.

[0024] Satisfying the spectral characteristics (i-4) means that it has excellent transmittance in the visible light range, especially in the blue band. 430-500(0)AVE This is preferably 89% or more, and more preferably 90% or more. To satisfy the spectral characteristics (i-4), for example, UV dyes or IR dyes with high transmittance in the visible light band can be used.

[0025] Meeting the spectral characteristics (i-5) means that it has excellent light-shielding properties in the ultraviolet region and excellent transmittance in the visible light region. Wavelength UV50 (0) The wavelength is preferably in the range of 400-430 nm. To satisfy the spectral characteristics (i-5), for example, one could use a UV dye with the maximum absorption wavelength in an appropriate wavelength range, or adjust the cut edge of the dielectric multilayer film which is the reflective layer.

[0026] Spectral characteristics (i-6) in ΔUV 70-10(0) and ΔUV 70-10(30)This represents the steepness (rise) of the transmittance curve around the UV absorption onset band of 350-450 nm at incident angles of 0 and 30 degrees. Satisfying spectral characteristics (i-6) means that, even at high incident angles, the shift in the steepness of the transmittance curve is minimal, resulting in excellent color reproduction around the UV absorption onset band of 350-450 nm. ΔUV 70-10(0) and ΔUV 70-10(30) The absolute value of the difference is preferably 2.0 nm or less. To satisfy the spectral characteristics (i-6), for example, one can use a UV dye that has its maximum absorption wavelength within an appropriate wavelength range and exhibits excellent steepness.

[0027] By satisfying spectral characteristics (i-7) and (i-8), it means that the light shielding properties in the near-infrared region and the transmittance properties in the visible light region are excellent, and the shift in the transmittance curve is small even at high incident angles around the near-infrared absorption start band, resulting in excellent color reproduction. Wavelength IR50 (0) The wavelength is preferably in the range of 620 to 660 nm. Wavelength IR50 (30) The wavelength is preferably in the range of 620 to 660 nm. Wavelength IR50 (0) and wavelength IR50 (30) The absolute value of the difference is preferably 4 nm or less. To satisfy spectral characteristics (i-7) and (i-8), for example, an IR dye having the maximum absorption wavelength within an appropriate wavelength range can be used.

[0028] The optical filter of the present invention preferably further satisfies the following spectral characteristics (i-9). (i-9) Said wavelength UV10 (0) and wavelength UV70 (0) The absolute value of the difference is 13 nm or less. By satisfying the spectral characteristics (i-9), the slope of the spectral transmittance curve from the near-ultraviolet region (the shielding region) to the visible light region (the transmitting region) is steep, meaning that both high shielding in the near-ultraviolet region and high transmittance in the visible light region can be achieved. Wavelength UV10(0) and wavelength UV70 (0) The absolute value of the difference is more preferably 12 nm or less. To satisfy the spectral characteristics (i-9), for example, one can use a UV dye with excellent steepness.

[0029] The optical filter of the present invention preferably further satisfies the following spectral characteristics (i-10) and (i-11). (i-10) Maximum transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm and an incident angle of 0 degrees. 360-400(0)MAX less than 5% (i-11) Maximum transmittance T in the spectral transmittance curve at wavelengths of 350-390 nm and an incident angle of 50 degrees 350-390(50)MAX less than 5%

[0030] Satisfying the spectral characteristics (i-10) means that it has high light-shielding properties in the ultraviolet light region with wavelengths of 360-400 nm. 360-400(0)MAX Preferably, it is 4% or less. To satisfy the spectral characteristics (i-10), for example, one can use a dye with high absorption capacity in the near-ultraviolet region.

[0031] Satisfying the spectral characteristics (i-11) means that light leakage is less likely to occur even at high incident angles in the ultraviolet light region of 350-390 nm wavelength, resulting in high light-shielding properties. 350-390(50)MAX Preferably, it is 4% or less. To satisfy the spectral characteristics (i-11), for example, one can use a dye with high absorption capacity in the near-ultraviolet region.

[0032] The substrate and dielectric multilayer film will be described below. This filter is designed such that, for example, the substrate has the ability to absorb ultraviolet and near-infrared light, and the absorption characteristics of the substrate and the reflection characteristics of the dielectric multilayer film satisfy the above spectral characteristics (i-1) to (i-8).

[0033] <Base material> In the optical filter of the present invention, the substrate has a resin film containing a resin, a UV dye 1, and an IR dye.

[0034] <Resin film> The resin film preferably satisfies all of the following spectral characteristics (iii-1) to (iii-9). (iii-1) Internal transmittance T at a wavelength of 360 nm 360 less than 25% (iii-2) Internal transmittance T at a wavelength of 370 nm 370 less than 10% (iii-3) Internal transmittance T at a wavelength of 380 nm 380 less than 4% (iii-4) Average internal transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm 360-400AVE less than 15% (iii-5) Average internal transmittance T in the spectral transmittance curve at wavelengths of 400-430 nm 400-430AVE over 40% (iii-6) Average internal transmittance T in the spectral transmittance curve at wavelengths of 430-500 nm 430-500AVE over 90% (iii-7) In the spectral transmittance curve at wavelengths of 350 to 450 nm, the absolute difference between the wavelength UV10 when the internal transmittance is 10% and the wavelength UV70 when the internal transmittance is 70% is 17 nm or less. (iii-8) Internal transmittance T at wavelength 700 nm. 700 less than 5% (iii-9) In the spectral transmittance curve at wavelengths of 600-700 nm, the wavelength IR50, where the internal transmittance is 50%, is at 610-670 nm.

[0035] By satisfying spectral characteristics (iii-1) to (iii-4), an optical filter can be obtained that exhibits high light shielding in the near-ultraviolet region and maintains its near-ultraviolet light shielding performance even at high incident angles. Internal transmittance T 360 It is more preferable to have 20% or less. Internal transmittance T 370 It is more preferably 7% or less. Internal transmittance T 380 It is more preferably 3.5% or less. Average internal transmittance T 360-400AVE It is more preferably 13% or less.

[0036] By satisfying the spectral characteristics (iii-5) to (iii-6), an optical filter excellent in transmittance in visible light, particularly in the blue light region, can be obtained. T 400-430AVE is more preferably 42% or more. T 430-500AVE is more preferably 92% or more.

[0037] By satisfying the spectral characteristic (iii-7), an optical filter excellent in sharpness can be obtained. The absolute value of the difference between the wavelength UV10 and the wavelength UV70 is more preferably 15 nm or less.

[0038] By satisfying the spectral characteristics (iii-8) to (iii-9), an optical filter excellent in light shielding property in the near-infrared light region can be obtained. Internal transmittance T 700 is more preferably 3% or less. The wavelength IR50 is more preferably in the range of 620 to 670 nm.

[0039] In order to satisfy the spectral characteristics (iii-1) to (iii-7), the compound shown in the following formula (S) can be used as a UV dye. In order to satisfy the spectral characteristics (iii-8) to (iii-9), the squarylium compound described later can be used as an IR dye.

[0040] <UV dye> UV Dye 1 is a near-ultraviolet absorbing dye having a maximum absorption wavelength in the range of 360 to 390 nm in the resin. By containing such a dye, ultraviolet light can be effectively cut. UV Dye 1 preferably has specific spectral characteristics in the resin. Specifically, in the spectral internal transmittance curve of the coating film obtained by dissolving UV Dye 1 in the resin and coating it on an alkali glass plate, it is preferable to satisfy all of the following spectral characteristics (ii-1) to (ii-3). Note that the resin is preferably the same as the resin contained in the substrate.

[0041] (ii-1) Absorbance at the maximum absorption wavelength is 0.1 ( / mass%·μm) or higher (ii-2) In the spectral internal transmittance curve of the coating film, in which the internal transmittance at the maximum absorption wavelength is 1%, the average internal transmittance T at wavelengths of 350-400 nm 350-400AVE less than 13% (ii-3) In the spectral internal transmittance curve of the coated film normalized to have an internal transmittance of 1% at the maximum absorption wavelength, the absolute difference between the wavelength UV10 when the internal transmittance at wavelengths 350-450 nm is 10 nm or less and the wavelength UV70 when the internal transmittance is 70% is 10 nm or less.

[0042] In the spectral characteristics (ii-1), absorbance ( / mass%·μm) refers to the absorbance per 1 mass% of dye content and per 1 μm of film thickness. An absorbance of 0.1 or higher indicates that UV dye 1 has high absorption capacity, and sufficient light shielding can be achieved even with a small amount of dye. The absorbance is preferably 0.12 ( / mass%·μm) or higher.

[0043] Spectral characteristics (ii-2) mean that it can absorb light across a wide wavelength range of 350-400 nm. T 350-400AVE Preferably, it is 11% or less.

[0044] Spectral characteristics (ii-3) mean that the slope of the spectral transmittance curve is steep from the near-ultraviolet region, which is the light-shielding region, to the visible light region, which is the light-transmitting region. The absolute value of the difference between the wavelengths UV10 and UV70 is preferably 9.5 nm or less.

[0045] As UV dye 1, a cyanine compound represented by the following formula (S) is preferred from the viewpoint of easily satisfying the spectral characteristics (ii-1) to (ii-3) and from the viewpoint of having an effect of suppressing the degradation of the IR dye. IR dyes are generally prone to degradation when used in combination with UV dyes, but this can be prevented by using a cyanine compound represented by formula (S) as the UV dye.

[0046] [Chemical formula]

[0047] [The symbols in the above formula are as follows. R 1 and R 2 each independently represent an alkyl group having 1 to 4 carbon atoms. R 3 to R 10 each independently represent a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxy group, a phenyl group, an alkyl group having 1 to 10 carbon atoms which may have a substituent, an alkoxy group having 1 to 10 carbon atoms which may have a substituent, an acyloxy group having 1 to 10 carbon atoms which may have a substituent, -NR 11 R 12 (R 11 , R 12 each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent, -C(=O)-R 13 (R 13 is an alkyl group having 1 to 10 carbon atoms which may have a substituent or an aryl group having 6 to 11 carbon atoms), -SO2-R 14 (R 14 is an alkyl group having 1 to 10 carbon atoms which may have a substituent or an aryl group having 6 to 11 carbon atoms)), or -SO2-R 15 (R 15 [[ID=4l]] is an alkyl group having 1 to 10 carbon atoms which may have a substituent or an aryl group having 6 to 11 carbon atoms, or -NR 16 R 17 (R 16 , R 17 each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent. )]. X and Y each independently represent O, S, or -C(CH3)2. An - represents a monovalent anion.]

[0048] < / R 1 and R 2From the viewpoint of ease of synthesis, each is independently preferably a methyl group or an ethyl group.

[0049] R 3 ~R 10 Examples of the substituent in 3 ~R 10 include an alkyl group, a halogen atom or a phenyl group from the viewpoint of ease of synthesis. Among them, a t-butyl group is preferably included from the viewpoint of solubility in the resin. The number of carbon atoms of the substituent is included in the respective number of carbon atoms of R

[0050] R 3 is preferably a hydrogen atom from the viewpoint of ease of synthesis. R 4 is a hydrogen atom, a halogen atom, a cyano group, a nitro group, a phenyl group, an alkyl group having 1 to 10 carbon atoms which may have a substituent, -NH-C(=O)-R 13 (R 13 is preferably an alkyl group having 1 to 10 carbon atoms), -SO2-R 15 (R 15 is preferably an alkyl group having 1 to 10 carbon atoms), and particularly preferably an alkyl group having 4 to 10 carbon atoms from the viewpoint of solubility in the resin. Among them, a t-butyl group is particularly preferable. R 5 、R 6 、R 7 is preferably a hydrogen atom from the viewpoint of ease of synthesis. R 8 is preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a halogen atom or a phenyl group from the viewpoints of ease of synthesis and the range of the maximum absorption wavelength. R 9 、R 10 is preferably, independently of each other, a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a halogen atom from the viewpoints of ease of synthesis and the range of the maximum absorption wavelength. X and Y are preferably O from the viewpoint that the maximum absorption wavelength of the dye (S) falls within an appropriate wavelength range.

[0051] An - is PF6- [Rf-SO2] - [N(Rf-SO2)2] - , or BF4 - This is preferable. Rf represents an alkyl group substituted with at least one fluorine atom, preferably a perfluoroalkyl group having 1 to 8 carbon atoms, and particularly preferably -CF3. The anion structure yields a UV dye compound (S) with excellent light resistance.

[0052] More specifically, in formula (S), the atoms or groups bonded to each skeleton are those listed in the table below. Note that tBu stands for tert-butyl group, and Ph stands for phenyl group.

[0053] [Table 1]

[0054] As for compound (S), due to its solubility in resins and ease of synthesis, the anions are BF4. - PF6 - , or N(SO2CF3)2 - Compounds (S-7) and (S-8) are preferred, and the anion is BF4 - PF6 - , or N(SO2CF3)2 - The compound (S-8) has an anion PF6 - Compound (S-7) is particularly preferred.

[0055] Compound (S) can be produced by known methods described, for example, in Japanese Patent Publication No. 2011-102841, Japanese Patent No. 4702731, etc.

[0056] As the UV dye in the resin film, UV dye 1 may be used alone, or two or more may be used in combination. However, from the viewpoint of being able to more efficiently block ultraviolet light with a small amount, it is preferable to use two or more with different maximum absorption wavelengths in combination. The resin film preferably further contains UV dye 2, which has a maximum absorption wavelength of 390-405 nm in the resin and whose maximum absorption wavelength is 10 nm or more greater than that of UV dye 1.

[0057] As UV dye 2, merocyanine dyes represented by the following formula (M) are particularly preferred.

[0058] [ka]

[0059] The symbols in equation (M) are as follows:

[0060] R 1 This represents a monovalent hydrocarbon group having 1 to 12 carbon atoms, which may have substituents. Preferred substituents are alkoxy groups, acyl groups, acyloxy groups, cyano groups, dialkylamino groups, or chlorine atoms. The number of carbon atoms in the alkoxy groups, acyl groups, acyloxy groups, and dialkylamino groups is preferably 1 to 6.

[0061] R without substituents 1 Specifically, preferred are C1-C12 alkyl groups in which some of the hydrogen atoms may be substituted with an aliphatic ring, an aromatic ring, or an alkenyl group, C3-C8 cycloalkyl groups in which some of the hydrogen atoms may be substituted with an aromatic ring, an alkyl group, or an alkenyl group, and C6-C12 aryl groups in which some of the hydrogen atoms may be substituted with an aliphatic ring, an alkyl group, or an alkenyl group.

[0062] R 1 If the alkyl group is an unsubstituted alkyl group, it may be linear or branched, and its carbon number is more preferably 1 to 6.

[0063] R 1When the alkyl group has 1 to 12 carbon atoms, in which some of the hydrogen atoms are substituted with an aliphatic ring, an aromatic ring, or an alkenyl group, alkyl groups with 1 to 4 carbon atoms having a cycloalkyl group with 3 to 6 carbon atoms, alkyl groups with 1 to 4 carbon atoms substituted with a phenyl group are more preferred, and alkyl groups with 1 or 2 carbon atoms substituted with a phenyl group are particularly preferred. Note that an alkyl group substituted with an alkenyl group means an alkenyl group as a whole, but without an unsaturated bond between the 1st and 2nd positions, such as an allyl group or a 3-butenyl group.

[0064] Preferred R 1 Q is a C1-C6 alkyl group in which some of the hydrogen atoms may be substituted with cycloalkyl groups or phenyl groups. Particularly preferred Q 1 This refers to an alkyl group having 1 to 6 carbon atoms, specifically including methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups.

[0065] R 2 ~R 5 Each of these independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. The alkyl group and alkoxy group preferably have 1 to 6 carbon atoms, and more preferably 1 to 4 carbon atoms.

[0066] R 2 and R 3 Preferably, at least one of them is an alkyl group, and more preferably, both are alkyl groups. 2 and R 3 If it is not an alkyl group, a hydrogen atom is more preferable. 2 and R 3 Alkyl alkyl groups having 1 to 6 carbon atoms are particularly preferred.

[0067] R 4 and R 5 At least one of them is preferably a hydrogen atom, and both are more preferably hydrogen atoms. 4 or R 5 If it is not a hydrogen atom, an alkyl group having 1 to 6 carbon atoms is preferred.

[0068] Y is R 6 and R 7 This represents a methylene group or oxygen atom substituted with [a specific component]. R 6 and R 7 Each of these independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms.

[0069] X represents one of the divalent groups shown in the following formulas (X1) to (X5).

[0070] [ka]

[0071] R 8 and R 9 Each of these independently represents a monovalent hydrocarbon group having 1 to 12 carbon atoms, which may have substituents, and R 10 ~R 19 Each of these independently represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms, which may have substituents. R 8 ~R 19 As substituents, R 1 Examples of substituents similar to those in R include similar substituents, and preferred embodiments are also similar. 8 ~R 19 If is a hydrocarbon group without substituents, then R without substituents 1 Similar embodiments can be cited.

[0072] In equation (X1), R 8 and R 9 The groups may be different, but the same group is preferred. 8 and R 9 When is an unsubstituted alkyl group, it may be linear or branched, and the number of carbon atoms is more preferably 1 to 6.

[0073] Preferred R 8 and R 9These are all C1-C6 alkyl groups in which some of the hydrogen atoms may be substituted with cycloalkyl groups or phenyl groups. Particularly preferred R 8 and R 9 These are all alkyl groups having 1 to 6 carbon atoms, and specifically, examples include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, etc.

[0074] In equation (X2), R 10 and R 11 In all cases, alkyl groups having 1 to 6 carbon atoms are more preferred, and the same alkyl group is particularly preferred.

[0075] In equation (X3), R 12 and R 15 Preferably, these are hydrogen atoms or unsubstituted alkyl groups having 1 to 6 carbon atoms. R is two groups bonded to the same carbon atom. 13 and R 14 These are preferably hydrogen atoms or alkyl groups having 1 to 6 carbon atoms.

[0076] In formula (X4), the two groups R bonded to the same carbon atom 16 and R 17 and R 18 and R 19 These are preferably hydrogen atoms or alkyl groups having 1 to 6 carbon atoms.

[0077] The compounds represented by formula (M) are preferably compounds in which Y is an oxygen atom and X is a group (X1), a group (X2), or a group (X5), and compounds in which Y is an unsubstituted methylene group and X is a group (X1), a group (X2), or a group (X5).

[0078] Specific examples of compound (M) include the compounds shown in the table below.

[0079] [Table 2]

[0080] As for compound (M), compounds (M-2), (M-8), (M-9), (M-13), and (M-20) are preferred due to their appropriate solubility in the resin and maximum absorption wavelength.

[0081] Compound (M) can be produced by known methods, for example, as described in Japanese Patent Publication No. 6504176.

[0082] The content of UV dye 1 in the resin film is preferably in a range where the product of the content of UV dye 1 and the thickness of the resin film is preferably 15 (mass%·μm) or less, more preferably 14.5 (mass%·μm) or less, and particularly preferably 14.0 (mass%·μm) or less. If the amount of UV dye 1 added is too high, it can lead to a decrease in resin properties, which may result in reduced adhesion to dielectric multilayer films and glass. In addition, the glass transition temperature of the resin may decrease, raising concerns about heat resistance. These problems can be prevented if the product of the dye content and the thickness of the resin film is within the above range. Furthermore, from the viewpoint of satisfying the desired spectral characteristics, the product of the content and thickness is preferably 3.0 (mass%·μm) or more, more preferably 5.0 (mass%·μm) or more.

[0083] From the viewpoint of satisfying the above range, the content of UV dye 1 in the resin film is preferably 2.0 to 15.0 parts by mass, more preferably 3.0 to 14.0 parts by mass, per 100 parts by mass of resin. Within this range, the above problems can be avoided without degrading the resin properties.

[0084] When the resin film contains UV dye 1 and UV dye 2, for similar reasons, it is preferable to set the content of UV dye 2 such that the product of the total content of UV dye 1 and UV dye 2 and the thickness of the resin film is 15 (mass %·μm) or less, more preferably 14.5 (mass %·μm) or less, and particularly preferably 14.0 (mass %·μm) or less.

[0085] The content of UV dye 2 in the resin film is preferably 2.0 to 13.0 parts by mass, more preferably 3.0 to 11.0 parts by mass, per 100 parts by mass of resin.

[0086] In addition, the total content of UV dye 1 and UV dye 2 in the resin film is preferably 3.0 to 15.0 parts by mass, more preferably 5.0 to 14.0 parts by mass with respect to 100 parts by mass of the resin.

[0087] <IR dye> The IR dye is a near-infrared absorbing dye having a maximum absorption wavelength at 680 to 800 nm in the resin. By containing such a dye, infrared light can be effectively cut.

[0088] As the IR dye, at least one selected from the group consisting of squarylium dyes, cyanine dyes, phthalocyanine dyes, naphthalocyanine dyes, dithiol metal complex dyes, azo dyes, polymethine dyes, phthalide dyes, naphthoquinone dyes, anthraquinone dyes, indophenol dyes, pyrylium dyes, thiopyrylium dyes, croconium dyes, tetradehydrookorine dyes, triphenylmethane dyes, aminium dyes and diimonium dyes is preferable.

[0089] As the IR dye, it is preferable to contain at least one dye selected from squarylium dyes, phthalocyanine dyes, and cyanine dyes. Among these IR dyes, squarylium dyes and cyanine dyes are preferable from the spectroscopic viewpoint, and phthalocyanine dyes are preferable from the durability viewpoint.

[0090] The content of the NIR dye in the resin film is preferably 5 to 25 parts by mass, more preferably 5 to 20 parts by mass with respect to 100 parts by mass of the resin.

[0091] <Substrate structure> The substrate in this filter may have a single-layer structure or a multilayer structure. Also, as the material of the substrate, an organic material or an inorganic material may be used as long as it is a transparent material that transmits visible light of 400 to 700 nm, and there is no particular limitation. When the substrate has a single-layer structure, it is preferably a resin substrate made of a resin film containing a resin, a UV dye, and a NIR dye. When the substrate has a multilayer structure, it is preferable that a resin film containing a UV dye and an NIR dye is laminated on at least one main surface of the support. In this case, it is preferable that the support is made of a transparent resin or a transparent inorganic material.

[0092] As the resin, transparent resins are preferred, and examples include polyester resin, acrylic resin, epoxy resin, ene-thiol resin, polycarbonate resin, polyether resin, polyarylate resin, polysulfone resin, polyethersulfone resin, poly-p-phenylene resin, polyarylene ether phosphine oxide resin, polyamide resin, polyimide resin, polyamide-imide resin, polyolefin resin, cyclic olefin resin, polyurethane resin, and polystyrene resin. These resins may be used individually or in mixtures of two or more. Among these, polyimide resin is preferred because it has excellent visible light transmittance and a high glass transition temperature, which reduces thermal degradation of the dye.

[0093] Glass and crystalline materials are preferred as transparent inorganic materials. Examples of glass that can be used as a support include phthalate glass, phosphate glass, and other absorption-type glass containing copper ions (near-infrared absorbing glass), soda-lime glass, borosilicate glass, alkali-free glass, and quartz glass. Depending on the purpose, absorption glass is preferred, and from the viewpoint of absorbing infrared light, phosphate glass and boiling phosphate glass are preferred. When it is desired to capture a large amount of red light (600-700 nm), alkali glass, alkali-free glass, and quartz glass are preferred. Note that "phosphate glass" also includes silicate glass in which part of the glass skeleton is composed of SiO2.

[0094] As the glass, chemically strengthened glass may be used, obtained by ion exchange at a temperature below the glass transition temperature, in which alkali metal ions with small ionic radii (e.g., Li ions, Na ions) present on the main surface of the glass plate are replaced with alkali ions with larger ionic radii (e.g., Na ions or K ions for Li ions, and K ions for Na ions).

[0095] Examples of crystalline materials that can be used as supports include birefringent crystals such as quartz, lithium niobate, and sapphire.

[0096] As a support material, inorganic materials are preferred, particularly glass and sapphire, from the viewpoint of shape stability related to long-term reliability such as optical properties and mechanical properties, as well as handling during filter manufacturing.

[0097] The resin film can be formed by preparing a coating solution by dissolving or dispersing a dye, a resin or resin raw material component, and other components as needed in a solvent, coating this solution onto a support, drying it, and further curing it as needed. The support may be the support included in this filter, or it may be a releaseable support used only when forming the resin film. The solvent may be any dispersion medium or solvent that can stably disperse or dissolve the components.

[0098] Furthermore, the coating solution may contain a surfactant to improve voids caused by minute bubbles, indentations caused by the adhesion of foreign matter, and repulsion during the drying process. In addition, methods such as immersion coating, cast coating, or spin coating can be used for applying the coating solution. After applying the above coating solution to the support, a resin film is formed by drying. Furthermore, if the coating solution contains raw material components of a transparent resin, a curing treatment such as thermosetting or photocuring is performed.

[0099] Furthermore, the resin film can also be manufactured in film form by extrusion molding. When the substrate is a single-layer structure (resin substrate) consisting of a resin film containing a dye, the resin film can be used as the substrate as is. When the substrate is a multi-layer structure (composite substrate) having a support and a resin film laminated on at least one main surface of the support, the substrate can be manufactured by laminating this film onto the support and integrating it by heat pressing or the like.

[0100] The resin film may be present as one layer within the optical filter, or as two or more layers. If there are two or more layers, each layer may have the same or different configuration.

[0101] The thickness of the resin film is 3 μm or less, preferably 2.5 μm or less. Within this range, a uniform film with a small thickness distribution is easily obtained. Furthermore, from the viewpoint of obtaining desired spectral characteristics, the thickness is preferably 1.0 μm or more. When the resin film consists of multiple layers, it is preferable that the thickness of each layer satisfies the above range.

[0102] The shape of the substrate is not particularly limited and may be in the form of a block, plate, or film. Furthermore, the thickness of the substrate is preferably 300 μm or less, more preferably 50 to 300 μm, and particularly preferably 70 to 300 μm, from the viewpoint of preventing warping deformation that occurs during reliability fluctuations when a dielectric multilayer film is formed, or from handling considerations. Furthermore, the thickness of the substrate is preferably 120 μm or less when the substrate is a resin substrate containing resin and dye, due to the advantage of lowering the height, and preferably 50 μm or more from the viewpoint of reducing warping during multilayer film formation. When the substrate is a composite substrate comprising a support and a resin film, the thickness is preferably 70 μm to 110 μm.

[0103] <Dielectric multilayer film> In this filter, the dielectric multilayer film is laminated as the outermost layer on at least one main surface side of the substrate.

[0104] In this filter, it is preferable that at least one of the dielectric multilayer films is designed as a near-infrared reflective layer (hereinafter also referred to as the NIR reflective layer). The other dielectric multilayer film is preferably designed as an NIR reflective layer, a reflective layer having a reflection region other than the near-infrared region, or an anti-reflective layer.

[0105] The NIR reflective layer is a dielectric multilayer film designed to block near-infrared light. For example, the NIR reflective layer has wavelength selectivity, transmitting visible light and primarily reflecting near-infrared light outside the light-blocking region of the resin film. The reflective region of the NIR reflective layer may also include the light-blocking region of the resin film in the near-infrared region. The NIR reflective layer may be designed to further block light in wavelengths other than the near-infrared region, such as the near-ultraviolet region, as appropriate.

[0106] The NIR reflective layer preferably satisfies the following spectral characteristics. (v-1) Average transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm and an incident angle of 0 degrees 360-400(0)AVE less than 1% (v-2) Average transmittance T in the spectral transmittance curve at wavelengths of 430-500 nm and an incident angle of 0 degrees 430-500(0)AVE over 90% (v-3) Average transmittance T in the spectral transmittance curve at wavelengths of 750-1000 nm and an incident angle of 0 degrees 750-1000(0)AVE less than 2% (v-4) In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 0 degrees, the wavelength at which the transmittance is 50% is UV50, which is at 380-430 nm. (v-5) In the spectral transmittance curve for wavelengths of 650-750 nm and an incident angle of 0 degrees, the wavelength IR50, where the transmittance is 50%, is at 670-720 nm.

[0107] The NIR reflective layer is composed of a dielectric multilayer film made by stacking two or more dielectric films, for example, a low refractive index dielectric film, a medium refractive index dielectric film, and a high refractive index dielectric film. The high refractive index film preferably has a refractive index of 1.6 or higher, and more preferably 2.2 to 2.5. Examples of materials for the high refractive index film include Ta2O5, TiO2, TiO, and Nb2O5. Other commercially available products include OS50 (Ti3O5), OS10 (Ti4O7), OA500 (a mixture of Ta2O5 and ZrO2), and OA600 (a mixture of Ta2O5 and TiO2), all manufactured by Canon Optron. Of these, TiO2 is preferred in terms of film formation properties, reproducibility of refractive index, and stability.

[0108] The medium refractive index film preferably has a refractive index of 1.6 or higher and less than 2.2. Examples of materials for the medium refractive index film include ZrO2, Nb2O5, Al2O3, HfO2, and OM-4, OM-6 (a mixture of Al2O3 and ZrO2) and OA-100 sold by Canon Optron, as well as H4 and M2 (alumina antania) sold by Merck. Of these, Al2O3-based compounds and mixtures of Al2O3 and ZrO2 are preferred in terms of film formation properties, reproducibility in refractive index, and stability.

[0109] The low refractive index film preferably has a refractive index of less than 1.6, and more preferably 1.45 or more and less than 1.55. Examples of materials for the low refractive index film include SiO2 and SiO2. x N y、 Examples include MgF2. Other commercially available products include S4F and S5F (a mixture of SiO2 and AlO2) manufactured by Canon Optron. Of these, SiO2 is preferred in terms of reproducibility, stability, and cost-effectiveness in film formation.

[0110] Furthermore, it is preferable that the transmittance of the NIR reflective layer changes abruptly in the boundary wavelength region between the transmittance and shielding regions. For this purpose, the total number of layers of dielectric multilayer films constituting the reflective layer is preferably 15 or more, more preferably 25 or more, and even more preferably 30 or more. However, as the total number of layers increases, warping and other issues may occur, and the film thickness may increase, so the total number of layers is preferably 100 or less, more preferably 75 or less, and even more preferably 60 or less. In addition, the film thickness of the reflective layer is preferably 2 to 10 μm overall.

[0111] If the total number of layers and thickness of the dielectric multilayer film are within the above range, the NIR reflective layer can meet the miniaturization requirements and suppress incident angle dependence while maintaining high productivity. Furthermore, for the formation of the dielectric multilayer film, vacuum deposition processes such as CVD, sputtering, and vacuum evaporation, as well as wet deposition processes such as spraying and dipping, can be used.

[0112] The NIR reflective layer may provide predetermined optical properties with a single layer (a group of dielectric multilayer films) or with two layers. If there are two or more layers, each reflective layer may have the same or different configuration. When there are two or more reflective layers, they are usually composed of multiple reflective layers with different reflection bands. When two reflective layers are provided, one may be a near-infrared reflective layer that shields light in the short-wavelength band of the near-infrared region, and the other may be a near-infrared / near-ultraviolet reflective layer that shields light in both the long-wavelength band of the near-infrared region and the near-ultraviolet region.

[0113] Examples of anti-reflective layers include dielectric multilayer films, intermediate refractive index media, and moth-eye structures with gradually changing refractive indices. Among these, dielectric multilayer films are preferred from the viewpoint of optical efficiency and productivity. The anti-reflective layer is obtained by alternately stacking dielectric films, similar to the reflective layer.

[0114] This filter may also include other components, such as a component (layer) that provides absorption by inorganic nanoparticles that control the transmission and absorption of light in a specific wavelength range. Specific examples of inorganic nanoparticles include ITO (Indium Tin Oxides), ATO (Antimony-doped Tin Oxides), cesium tungstate, and lanthanum boride. ITO nanoparticles and cesium tungstate nanoparticles have high transmittance of visible light and light absorption over a wide range in the infrared wavelength region exceeding 1200 nm, and can therefore be used when shielding against such infrared light is required.

[0115] This filter, when used in imaging devices such as digital still cameras, can provide an imaging device with excellent color reproduction. An imaging device using this filter comprises a solid-state image sensor, an imaging lens, and this filter. This filter can be used, for example, by being placed between the imaging lens and the solid-state image sensor, or by being directly attached to the solid-state image sensor, imaging lens, etc. of the imaging device via an adhesive layer.

[0116] As described above, this specification discloses the following optical filters, etc. [1] An optical filter comprising a substrate and a dielectric multilayer film laminated as the outermost layer on at least one main surface side of the substrate, The substrate comprises a resin, a UV dye 1 having a maximum absorption wavelength of 360-390 nm in the resin, and an IR dye having a maximum absorption wavelength of 680-800 nm in the resin, and has a resin film with a thickness of 3 μm or less. The optical filter is an optical filter that satisfies all of the following spectral characteristics (i-1) to (i-8). (i-1) Average transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm and an incident angle of 0 degrees 360-400(0)AVE less than 0.5% (i-2) Average transmittance T in the spectral transmittance curve at wavelengths of 350-390 nm and an incident angle of 50 degrees 350-390(50)AVE less than 0.5% (i-3) Average transmittance T in the spectral transmittance curve at wavelengths of 400-430 nm and an incident angle of 0 degrees 400-430(0)AVE over 35% (i-4) Average transmittance T in the spectral transmittance curve at wavelengths of 430-500 nm and an incident angle of 0 degrees 430-500(0)AVE over 88% (i-5) In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 0 degrees, the wavelength at which the transmittance is 50% is UV50 (0) It is located at 400-430nm. (i-6) In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 0 degrees, when the transmittance is 10% at the wavelength UV10 (0) And, when the transmittance is 70%, the wavelength is UV70 (0) The absolute value of the difference between the two is ΔUV 70-10(0) year, In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 30 degrees, the wavelength UV10 when the transmittance is 10% (30) And, when the transmittance is 70%, the wavelength is UV70 (30) The absolute value of the difference between the two is ΔUV 70-10(30) In that case, ΔUV 70-10(0) and ΔUV 70-10(30) The absolute value of the difference is 2.5 nm or less. (i-7) In the spectral transmittance curve for wavelengths of 600-700 nm and an incident angle of 0 degrees, the wavelength at which the transmittance is 50% is IR50. (0) The wavelength IR50 is located at 610-670 nm, and in the spectral transmittance curve at wavelengths of 600-700 nm and an incident angle of 30 degrees, the transmittance is 50%. (30) It is located at 610-670nm. (i-8) The aforementioned wavelength IR50 (0) and wavelength IR50 (30) The absolute value of the difference is 5 nm or less. [2] The optical filter according to [1], wherein the optical filter further satisfies the following spectral characteristics (i-9). (i-9) Said wavelength UV10 (0) and wavelength UV70 (0) The absolute value of the difference is 13 nm or less. [3] The optical filter according to [1] or [2], wherein the product of the content of UV dye 1 in the resin film and the thickness of the resin film is 15 (mass %·μm) or less. [4] The resin film further contains a UV dye 2 which has a maximum absorption wavelength of 390 to 405 nm in the resin and whose maximum absorption wavelength is 10 nm or more greater than that of the UV dye 1. An optical filter according to any one of [1] to [3], wherein the product of the total content of UV dye 1 and UV dye 2 in the resin film and the thickness of the resin film is 15 (mass %·μm) or less. [5] The optical filter according to any one of [1] to [4], wherein the UV dye 1 is dissolved in the resin and coated onto an alkali glass plate, and the spectral internal transmittance curve of the coating satisfies all of the following spectral characteristics (ii-1) to (ii-3). (ii-1) Absorbance at the maximum absorption wavelength is 0.1 ( / mass%·μm) or higher (ii-2) In the spectral internal transmittance curve of the coating film, in which the internal transmittance at the maximum absorption wavelength is 1%, the average internal transmittance T at wavelengths of 350-400 nm 350-400AVE less than 13% (ii-3) In the spectral internal transmittance curve of the coated film normalized to have an internal transmittance of 1% at the maximum absorption wavelength, the absolute difference between the wavelength UV10 when the internal transmittance at wavelengths 350-450 nm is 10 nm or less and the wavelength UV70 when the internal transmittance is 70% is 10 nm or less. [6] The optical filter according to any one of [1] to [5], wherein the UV dye 1 is a cyanine compound represented by the following formula (S).

[0117] [ka]

[0118] [The symbols used in the above formula are as follows: R 1 , R 2 Each of these independently represents an alkyl group having 1 to 4 carbon atoms. R 3 ~R 10 Each of these independently comprises a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phenyl group, an optionally substituted C1-C10 alkyl group, an optionally substituted C1-C10 alkoxy group, an optionally substituted C1-C10 acyloxy group, and -NR. 11 R 12 (R 11 ,R 12 Each of these independently comprises a hydrogen atom, a C1-C10 alkyl group which may have substituents, and -C(=O)-R 13 (R 13 (wherein C1-C10 alkyl group or C6-C11 aryl group may have substituents), -SO2-R 14 (R 14() is a C1-C10 alkyl group or a C6-C11 aryl group which may have substituents), or -SO2-R 15 (R 15 -NR is a C1-C10 alkyl group or a C6-C11 aryl group, which may have substituents. 16 R 17 (R 16 ,R 17 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, which may have substituents. X and Y each independently represent O, S, or -C(CH3)2. An - This represents a monovalent anion. [7] The optical filter according to [6], wherein X and Y are O in the cyanine compound represented by formula (S). [8] An optical filter according to any one of [1] to [7], wherein the resin film satisfies all of the following spectral characteristics (iii-1) to (iii-9). (iii-1) Internal transmittance T at a wavelength of 360 nm 360 less than 25% (iii-2) Internal transmittance T at a wavelength of 370 nm 370 less than 10% (iii-3) Internal transmittance T at a wavelength of 380 nm 380 less than 4% (iii-4) Average internal transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm 360-400AVE less than 15% (iii-5) Average internal transmittance T in the spectral transmittance curve at wavelengths of 400-430 nm 400-430AVE over 40% (iii-6) Average internal transmittance T in the spectral transmittance curve at wavelengths of 430-500 nm 430-500AVE over 90% (iii-7) In the spectral transmittance curve for wavelengths of 350-450 nm, the absolute difference between the wavelength UV10 when the internal transmittance is 10% and the wavelength UV70 when the internal transmittance is 70% is 17 nm or less. (iii-8) Internal transmittance T at a wavelength of 700 nm 700 less than 5% (iii-9) In the spectral transmittance curve at wavelengths of 600-700 nm, the wavelength IR50, where the internal transmittance is 50%, is at 610-670 nm. [9] The optical filter according to [4], wherein the UV dye 2 comprises a merocyanine compound.

[10] The optical filter according to any one of [1] to [9], wherein the IR dye comprises at least one compound selected from squarylium compounds, phthalocyanine compounds, and cyanine compounds.

[11] The optical filter according to any one of [1] to

[10] , wherein the resin is a transparent resin.

[12] The optical filter according to

[11] , wherein the transparent resin comprises a polyimide resin. An imaging device equipped with an optical filter as described in any of

[13] , [1], to

[12] . [Examples]

[0119] Next, the present invention will be described in more detail with reference to examples. A UV-Vis-Near-Infrared spectrophotometer (Hitachi High-Technologies Corporation, Model UH-4150) was used to measure each optical characteristic. Unless otherwise specified, the spectral characteristics are measured at an incident angle of 0 degrees (perpendicular to the principal plane).

[0120] The dyes used in each example are as follows: Compounds 1-18 are UV dyes, and compound 19 is an NIR dye. Compounds 1-4 (cyanine compounds): These were synthesized by the method described below, with reference to Japanese Patent Publication No. 2011-102841 and Japanese Patent No. 4702731. Compound 5 (azo compound): Synthesized with reference to Japanese Patent Publication No. 6256335. Compound 6 (triazine compound): Tinuvin 928, manufactured by BASF Japan. Compound 7: Tinuvin 460, manufactured by BASF Japan. Compounds 8-12 (merocyanine compounds): Synthesized with reference to Japanese Patent Publication No. 6504176. Compound 13: Nikkafluor U1, manufactured by Nippon Chemical Industrial Co., Ltd. Compound 14: Nikkafluor MCT, manufactured by Nippon Chemical Industrial Co., Ltd. Compound 15 (Cyanine compound): SMP-416, manufactured by Hayashibara Chemical Co., Ltd. Compound 16 (Cyanine compound): SMP-370, manufactured by Hayashibara Chemical Co., Ltd. Compound 17: Kayalight B, manufactured by Nippon Kayaku Co., Ltd. Compound 18: Kayalight 408, manufactured by Nippon Kayaku Co., Ltd. Compound 19 (squallium compound): Synthesized with reference to Japanese Patent Publication No. 6197940.

[0121] [ka]

[0122] [ka]

[0123] [ka]

[0124] <Synthesis of Compound 1>

[0125] [ka]

[0126] (Synthesis of compound B) Compound A (5.0 g), acetic anhydride (3.4 g), and ethyl acetate (60 mL) were added to a 500 mL round-bottom flask and reacted at room temperature for 2 hours. After the reaction was complete, the precipitated solid was filtered and collected to obtain 5.5 g (88%) of compound B. (Synthesis of compound C) Compound B (5.0 g), phosphoryl chloride (5.6 g), and chloroform (13 mL) were added to a 300 mL round-bottom flask, and the mixture was reacted under reflux for 2 hours. After the reaction was complete, the mixture was allowed to return to room temperature, and the reaction was stopped by pouring the reaction solution into ice water. After extraction, the mixture was purified by column chromatography to obtain 2.5 g (53%) of compound C. (Synthesis of compound D) Compound C (2.5 g), iodomethane (7.4 g), and DMF (15 mL) were added to a 300 mL round-bottom flask, and the mixture was reacted at 80 degrees Celsius for 2 hours. After the reaction was complete, the mixture was allowed to return to room temperature, ethyl acetate was added, and the precipitated solid was filtered and collected to obtain 2.9 g (77%) of compound D. (Synthesis of compound E) Compound A (28g), tetramethylthiuram disulfide (24g), potassium carbonate (69g), and DMF (500mL) were added to a 1L round-bottom flask, and the mixture was reacted under reflux for 15 hours. After the reaction was complete, the mixture was allowed to return to room temperature, and aqueous ammonium chloride solution was added to stop the reaction. After extraction, the mixture was purified by column chromatography to obtain 25g (71%) of compound E. (Synthesis of compound F) Compound E (25g), iodomethane (17g), potassium carbonate (40g), and ethyl acetate (100mL) were added to a 1L round-bottom flask, and the mixture was reacted at room temperature for 3 hours. After the reaction was complete, water was added to stop the reaction. After extraction, the solvent was removed to obtain 28g (quant.) of compound F. (Synthesis of compound G) Compound F (28g) and methyl p-toluenesulfonate (45g) were added to a 1L round-bottom flask and reacted at 130°C for 2 hours. After the reaction was complete, the mixture was allowed to return to room temperature, THF was added, and the precipitated solid was filtered and collected to obtain 34g (70%) of compound G. (Synthesis of compound H) Compound D (15g), compound G (19g), triethylamine (6.9g), and acetonitrile (90mL) were added to a 500mL round-bottom flask, and the mixture was reacted under reflux for 2 hours. After the reaction was complete, the mixture was returned to room temperature, and the precipitated solid was collected by filtration to obtain 15g (62%) of compound H. (Synthesis of Compound 1) To a 300 mL eggplant flask, compound H (3.0 g), potassium hexafluorophosphate (2.1 g), acetone (25 mL), methanol (25 mL), and water (25 mL) were added, and the mixture was reacted at room temperature for 3 hours. After the reaction was completed, it was purified by column chromatography to obtain 2.7 g (86%) of compound 1.

[0127] <Synthesis of Compound 2>

[0128]

Chemical formula

[0129] To a 300 mL eggplant flask, compound H (3.0 g), sodium tetrafluoroborate (2.0 g), acetone (25 mL), methanol (25 mL), and water (25 mL) were added, and the mixture was reacted at room temperature for 3 hours. After the reaction was completed, it was purified by column chromatography to obtain 2.0 g (72%) of compound 2.

[0130] <Synthesis of Compound 3>

[0131]

Chemical formula

[0132] To a 300 mL eggplant flask, compound H (3.0 g), lithium bis(trifluoromethanesulfonyl)imide (3.3 g), acetone (25 mL), methanol (25 mL), and water (25 mL) were added, and the mixture was reacted at room temperature for 3 hours. After the reaction was completed, it was purified by column chromatography to obtain 3.6 g (92%) of compound 3.

[0133] <Synthesis of Compound 4>

[0134]

Chemical formula

[0135] (Synthesis of Compound J) Compound I (12 g), iodoethane (56 g), and DMF (45 mL) were added to a 300 mL round-bottom flask, and the mixture was reacted at 90 degrees Celsius for 15 hours. After the reaction was complete, ethyl acetate was added, and the precipitated solid was filtered and collected to obtain 24 g (91%) of compound J. (Synthesis of compound K) Compound J (7.1 g), compound G (10 g), triethylamine (3.7 g), and acetonitrile (50 mL) were added to a 500 mL round-bottom flask, and the mixture was reacted under reflux for 2 hours. After the reaction was complete, the mixture was purified by column chromatography to obtain 10 g (87%) of compound K. (Synthesis of Compound 4) Compound K (3.0 g), potassium hexafluorophosphate (2.3 g), acetone (25 mL), methanol (25 mL), and water (25 mL) were added to a 300 mL round-bottom flask, and the mixture was reacted at room temperature for 3 hours. After the reaction was complete, the mixture was purified by column chromatography to obtain 1.5 g (48%) of compound 4.

[0136] <Spectral properties of the pigment in the resin (in the coating film)> [Example 1-1] Polyimide resin (C-3G30G, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was dissolved in an organic solvent (cyclohexanone:γ-butyrolactone = 1:1 mass ratio) at a concentration of 8.5% by mass. Compound 1 was added to the polyimide resin solution prepared above in an amount of 7.5 parts by mass per 100 parts by mass of resin, and the mixture was stirred for 2 hours while heating at 50°C. The dye-containing resin solution was spin-coated onto a glass substrate (alkali glass, Schott D263) to obtain a coating film with a thickness of 1 μm.

[0137] [Examples 1-2 to 1-18] A coating film was prepared in the same manner as in Example 1-1, except that compounds 2-18 were used instead of compound 1. (However, compound 5 was added in an amount of 4 parts by mass per 100 parts by mass of resin.)

[0138] For each coated glass substrate obtained, transmission spectroscopy (incident angle 0 degrees) and reflection spectroscopy (incident angle 5 degrees) were measured using a spectrophotometer in the wavelength range of 350 nm to 1200 nm. Using the obtained spectral transmittance curves and spectral reflectance curves, spectral internal transmittance curves were calculated. Furthermore, the absorbance at the maximum absorption wavelength and the spectral transmittance curve normalized to 1% of the internal transmittance at the maximum absorption wavelength were obtained when the dye addition amount was 1% by mass. The results are shown in the table below. Examples 1-1 to 1-18 are for reference only.

[0139] [Table 3]

[0140] Based on the above results, the coated films of Examples 1-1 to 1-4, which contain any of compounds 1 to 4 as UV dyes, have a maximum absorption wavelength of 360 to 390 nm and an absorbance of 0.1 or higher, indicating high absorption capacity and an average internal transmittance T 350-400AVE Since the internal transmittance is 13% or less, it exhibits excellent light-blocking properties in the near-ultraviolet region. Furthermore, the absolute difference between the wavelength UV10 when the internal transmittance is 10% and the wavelength UV70 when the internal transmittance is 70% is 10 nm or less, indicating that the rise (slope) of the transmittance curve from the near-ultraviolet region to the visible light region is steep, meaning that the transmittance in the blue band is high.

[0141] <Spectral properties of resin films> [Example 2-1] Polyimide resin (C-3G30G, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was dissolved in an organic solvent (cyclohexanone:γ-butyrolactone = 1:1 mass ratio) at a concentration of 8.5% by mass. To the polyimide resin solution prepared above, 9 parts by mass of compound 1 and 5 parts by mass of compound 19 were added per 100 parts by mass of resin, and the mixture was stirred for 2 hours while heating at 50°C. The dye-containing resin solution was spin-coated onto a glass substrate (alkali glass, Schott D263) to obtain a resin film with a thickness of 1.5 μm.

[0142] [Examples 2-2 to 2-23] Instead of Compound 1, a dye compound described in the following table was used at the concentration shown in the following table, and a resin film was obtained in the same manner as in Example 2-1 except that the film thickness of the resin film was the value shown in the following table.

[0143] For each glass substrate with the obtained resin film, transmission spectroscopy (incident angle 0 degrees) and reflection spectroscopy (incident angle 5 degrees) in the wavelength range of 350 nm to 1200 nm were measured using a spectrophotometer. Using the obtained spectral transmittance curve and spectral reflectance curve, a spectral internal transmittance curve was calculated. The results are shown in the following table. In addition, the spectral internal transmittance curve of the resin film of Example 2-19 is shown in FIG. 5, the spectral internal transmittance curve of the resin film of Example 2-1 is shown in FIG. 6, and the spectral internal transmittance curve of the resin film of Example 2-8 is shown in FIG. 7, respectively. Note that Examples 2-1 to 2-23 are reference examples.

[0144]

Table 4

[0145] From the above results, the resin films of Examples 2-1 to 2-5 and Examples 2-19 to 2-23 showed excellent spectral characteristics in the near-ultraviolet region. Among them, Examples 2-19 to 2-22 in which two types of UV dyes with different maximum wavelength regions were used in combination achieved broad absorption. However, the resin films of Examples 2-2 and 2-21 had a large amount of UV dye added, and the resin film of Example 2-22 had a large film thickness of the resin film, resulting in a large product of the UV dye content and the film thickness of the resin film. The resin films of Examples 2-7 to 2-14 contained only a UV dye whose maximum absorption wavelength region deviated from the range of 360 to 390 nm, resulting in low shielding properties in the near-ultraviolet light region of 360 to 400 nm and low transmittance in the blue light region of 400 to 430 nm. The resin films of Examples 2-6 and 2-15 to 2-18 contained a UV dye with a small absorbance in the resin, that is, a weak absorption, resulting in low shielding properties in the near-ultraviolet light region of 360 to 400 nm.

[0146] <Spectral Characteristics of Optical Filter> [Example 3-1] A dielectric multilayer film (reflective film) consisting of 42 alternating layers of SiO2 and TiO2 was deposited on one main surface of a glass substrate (alkali glass, Schott D263) by vapor deposition. The spectral characteristics are shown in the table below. A resin film was prepared on the other surface of the glass substrate using the dye compounds in the amounts shown in the table below, in the same manner as in Example 2-1. Subsequently, a dielectric multilayer film (anti-reflective film) consisting of alternating layers of SiO2 and TiO2 was deposited on the resin film to create an optical filter.

[0147] [Examples 3-2 to 3-21] An optical filter was prepared in the same manner as in Example 3-1, except that the type and content of the dye compound and the thickness of the resin film were changed to the values ​​shown in the table below.

[0148] For each obtained optical filter, transmission spectroscopy (incident angles of 0, 30, and 50 degrees) was measured using a spectrophotometer in the wavelength range of 350 nm to 1200 nm, and the spectral characteristics of each filter were calculated. The results are shown in the table below. Furthermore, the spectral transmittance curves for the optical filter in Example 3-18 are shown in Figure 8, the spectral transmittance curve for the optical filter in Example 3-1 is shown in Figure 9, and the spectral transmittance curve for the optical filter in Example 3-6 is shown in Figure 10. Examples 3-1 to 3-3 and 3-18 to 3-20 are examples of actual cases. Examples 3-4 to 3-17 and 3-21 are comparative examples.

[0149] [Table 5]

[0150] [Table 6]

[0151] The results above show that the optical filters in Examples 3-1 to 3-3 and Examples 3-18 to 3-20 exhibit high transmittance of visible light and high shielding of near-infrared and ultraviolet light. In particular, the shielding of ultraviolet light did not decrease even at a high incidence angle of 50 degrees, and they showed good spectral characteristics. Among these, the optical filters in Examples 3-18 to 3-20, which used two types of UV dyes with different maximum absorption wavelength ranges, showed that they could shield the near-ultraviolet light region more broadly and deeply than Examples 3-1 to 3-3, even with the same amount of dye added as Examples 3-1 to 3-3, which used one type of UV dye. The optical filters in Examples 3-5 to 3-8 and 3-10 to 3-13 used either of the resin films 2-7 to 2-14, which had low shielding properties in the near-ultraviolet light region (360 to 400 nm) and low transmittance in the blue light region (400 to 430 nm). As a result, at least one of the shielding properties in the near-ultraviolet light region or the transmittance in the visible light region at high incidence angles was low. The optical filter in Example 3-9 showed a large difference in steepness between an incident angle of 0 degrees and 30 degrees. This is because the steepness of optical filter 3-9 at an incident angle of 0 degrees largely depends on the steepness of the dielectric multilayer film, resulting in excellent steepness. On the other hand, at an incident angle of 30 degrees, the influence of the UV dye compound 10, which lacks sufficient steepness, becomes more significant, causing the steepness of the optical filter to decrease. The optical filters in Examples 3-4 and 3-14 to 3-17 used one of the resin films in Examples 2-6 and 2-15 to 2-18, which have low shielding properties in the near-ultraviolet light region of 360 to 400 nm, resulting in low shielding properties in the near-ultraviolet light region at high incidence angles. In the optical filter of Example 3-21, the resin film thickness exceeds 3 μm, and based on the results of the film thickness distribution evaluation described later, it is considered that a resin film with a uniform thickness cannot be obtained.

[0152] <Lightfastness Evaluation> [Example 4-1] A dielectric multilayer film (reflective film) consisting of 42 alternating layers of SiO2 and TiO2 was deposited on one main surface of a glass substrate (alkali glass, Schott D263) by vapor deposition. A resin film was prepared on the other surface of the glass substrate using the dye compounds in the amounts shown in the table below, in the same manner as in Example 2-1. Subsequently, a dielectric multilayer film (anti-reflective film) consisting of alternating layers of SiO2 and TiO2 was deposited on the resin film to create an optical filter.

[0153] [Examples 4-2 to 4-6] An optical filter was prepared in the same manner as in Example 4-1, except that the type and content of the dye compound were changed to the values ​​shown in the table below.

[0154] Each of the obtained optical filters was subjected to weather resistance testing using a Super Xenon Weathermeter manufactured by Suga Test Instruments Co., Ltd. The remaining percentage of the IR dye was calculated from the absorption coefficient at 700 nm before and after the weather resistance test. Incident surface: Irradiation from the anti-reflective coating side. Light intensity: 80,000 J / mm² as integrated light intensity in the wavelength range of 300-2450 nm. 2 The irradiation was applied in such a way that it would result in the desired outcome. The results are shown in the table below. Examples 4-1 to 4-6 are for reference only.

[0155] [Table 7]

[0156] As a guideline for maintaining the performance of an optical filter, an IR dye retention rate of 60% or more is considered necessary. In Examples 4-1 to 4-4, the optical filters in which one of the UV dye compounds 1 to 4 was present all achieved an IR dye retention rate of 60% or more. Since a similar dye retention rate was obtained compared to Example 4-6, which was not in coexistence with a UV dye, it was found that UV dye compounds 1 to 4 do not accelerate the degradation of the IR dye. On the other hand, in the optical filters of Example 4-5, in which UV dye compound 5 was present, IR dye degradation was accelerated, and the IR dye retention rate was significantly reduced.

[0157] <Evaluation of film thickness distribution> [Examples 5-1 to 5-4] Polyimide resin (C-3G30G, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was dissolved in an organic solvent (cyclohexanone:γ-butyrolactone = 1:1 mass ratio) at a concentration of 8.5% by mass. To the polyimide resin solution prepared above, compound 1 was added in an amount of 5 parts by mass, compound 8 in an amount of 5 parts by mass, and compound 19 in an amount of 5 parts by mass per 100 parts by mass of resin, and the mixture was stirred for 2 hours while heating at 50°C. The dye-containing resin solution was spin-coated onto a glass substrate (alkali glass, Schott D263) measuring 70 mm in length, 60 mm in width, and 0.2 mm in thickness at a rotation speed of 3000 rpm to obtain a resin film.

[0158] [Examples 5-2 to 5-4] The resin film was obtained in the same manner as in Example 5-1, except that the rotation speed was changed as shown in the table below.

[0159] For each resin-coated glass substrate obtained as described above, the film thickness was measured at nine points in the center of each of the nine equally spaced areas within the surface. The average of the nine measurement results was calculated, and if the ratio to the average ((measured value / average value) × 100) was between 95% and 105%, it was determined that the film thickness was uniform and the film thickness distribution was good. The results are shown in the table below. Examples 5-1 to 5-4 are for reference only.

[0160] [Table 8]

[0161] In examples 5-1 to 5-3, where the average film thickness is 3 μm or less, all measured values ​​are within 95-105% of the average value, indicating that uniform film deposition is possible. In example 5-4, where the average film thickness exceeded 3 μm, all measured values ​​were above 95-105% of the average, resulting in a large film thickness distribution. From the above results, it was found that a uniform resin film can be obtained if the film thickness is 3 μm or less.

[0162] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on Japanese Patent Application No. 2021-135204, filed on August 20, 2021, the contents of which are incorporated herein by reference. [Industrial applicability]

[0163] The optical filter of the present invention has good ultraviolet light shielding characteristics, with good shielding of near-infrared light, good transmittance of visible light, and suppressed decrease in ultraviolet light shielding at high incidence angles. It is useful in applications such as information acquisition devices like cameras and sensors for transport aircraft, where performance has been improving in recent years. [Explanation of Symbols]

[0164] 1A, 1B, 1C, 1D... Optical filters, 10... Substrate, 11... Support, 12... Resin film, 30... Dielectric multilayer film

Claims

1. An optical filter comprising a substrate and a dielectric multilayer film laminated on at least one main surface side of the substrate, The substrate has a resin film, the resin film comprises a resin, a UV dye 1 having a maximum absorption wavelength of 360 to 390 nm in the resin, and an IR dye having a maximum absorption wavelength of 680 to 800 nm in the resin. The optical filter is an optical filter that satisfies all of the following spectral characteristics (i-1) to (i-8). (i-1) Average transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm and an incident angle of 0 degrees ３６０－４００（０）ＡＶＥ less than 0.5% (i-2) Average transmittance T in the spectral transmittance curve at wavelengths of 350-390 nm and an incident angle of 50 degrees ３５０－３９０（５０）ＡＶＥ less than 0.5% (i-3) Average transmittance T in the spectral transmittance curve at wavelengths of 400-430 nm and an incident angle of 0 degrees ４００－４３０（０）ＡＶＥ over 35% (i-4) Average transmittance T in the spectral transmittance curve at wavelengths of 430-500 nm and an incident angle of 0 degrees ４３０－５００（０）ＡＶＥ over 88% (i-5) In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 0 degrees, the wavelength UV50 at which the transmittance is 50% （０） It is located at 400-430 nm. (i-6) In the spectral transmittance curve for wavelengths of 350-450 nm and an incident angle of 0 degrees, when the transmittance is 10%, the wavelength UV10 （０） And, the wavelength UV70 when the transmittance is 70% （０） The absolute value of the difference between the two is ΔUV. ７０－１０（０） year, In the spectral transmittance curve with a wavelength of 350 to 450 nm and an incident angle of 30 degrees, the wavelength UV10 when the transmittance is 10% （３０） and the wavelength UV70 when the transmittance is 70% （３０） The absolute value of the difference between them is defined as ΔUV ７０－１０（３０） When this is done, ΔUV ７０－１０（０） and ΔUV ７０－１０（３０） The absolute value of the difference is 2.5 nm or less (i-7) In the spectral transmittance curve for wavelengths of 600-700 nm and an incident angle of 0 degrees, the wavelength IR50 is such that the transmittance is 50%. （０） The wavelength IR50 is located at 610-670 nm, and in the spectral transmittance curve at wavelengths of 600-700 nm and an incident angle of 30 degrees, the transmittance is 50%. （３０） It is located at 610-670 nm. (i-8) The wavelength IR50 （０） and wavelength IR50 （３０） The absolute value of the difference is 5 nm or less.

2. The optical filter according to claim 1, wherein the optical filter further satisfies the following spectral characteristics (i-9). (i-9) Said wavelength UV10 （０） and wavelength UV70 （０） The absolute value of the difference is 13 nm or less.

3. The optical filter according to claim 1, wherein the product of the content of UV dye 1 in the resin film and the thickness of the resin film is 15 (mass %・μm) or less.

4. The resin film further contains a UV dye 2 having a maximum absorption wavelength of 390 to 405 nm in the resin, and having a maximum absorption wavelength at least 10 nm greater than that of the UV dye 1. The optical filter according to claim 1, wherein the product of the total content of UV dye 1 and UV dye 2 in the resin film and the thickness of the resin film is 15 (mass %・μm) or less.

5. The optical filter according to claim 1, wherein the UV dye 1 satisfies all of the following spectral characteristics (ii-1) to (ii-3) in the spectral internal transmittance curve of a coating film obtained by dissolving the UV dye 1 in the resin and coating it on an alkali glass plate. (ii-1) Absorbance at the maximum absorption wavelength is 0.1 ( / mass%·μm) or higher (ii-2) In the spectral internal transmittance curve of the coating film, in which the internal transmittance at the maximum absorption wavelength is 1%, the average internal transmittance T at wavelengths of 350 to 400 nm ３５０－４００ＡＶＥ less than 13% (ii-3) In the spectral internal transmittance curve of the coated film normalized to have an internal transmittance of 1% at the maximum absorption wavelength, the absolute value of the difference between the wavelength UV10 when the internal transmittance at 350-450 nm is 10 nm or less and the wavelength UV70 when the internal transmittance is 70% is 10 nm or less.

6. The optical filter according to claim 1, wherein the UV dye 1 is a cyanine compound represented by the following formula (S). 【Chemistry 1】 [The symbols used in the above formula are as follows. R １ , R ２ Each of these independently represents an alkyl group having 1 to 4 carbon atoms. R ３ ~R １０ Each of these independently comprises a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phenyl group, an optionally substituted C1-C10 alkyl group, an optionally substituted C1-C10 alkoxy group, an optionally substituted C1-C10 acyloxy group, and -NR １１ R １２ (R １１ , R １２ Each of these independently comprises a hydrogen atom, a C1-C10 alkyl group which may have substituents, and -C(=O)-R １３ (R １３ (wherein C1-C10 alkyl group or C6-C11 aryl group may have substituents), -SO ２ -R １４ (R １４ (wherein C1-C10 alkyl group or C6-C11 aryl group may have substituents), or -SO ２ -R １５ (R １５ is an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 11 carbon atoms, or -NR １６ R １７ (R １６ , R １７ Each of these independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, which may have substituents. X and Y are independently O, S, or -C (CH) ３ ) ２ It represents. An － This represents a monovalent anion.

7. The optical filter according to claim 6, wherein X and Y are O in the cyanine compound represented by formula (S).

8. The optical filter according to claim 1, wherein the resin film satisfies all of the following spectral characteristics (iii-1) to (iii-9). (iii-1) Internal transmittance T at a wavelength of 360 nm ３６０ less than 25% (iii-2) Internal transmittance T at a wavelength of 370 nm ３７０ less than 10% (iii-3) Internal transmittance T at a wavelength of 380 nm ３８０ less than 4% (iii-4) Average internal transmittance T in the spectral transmittance curve at wavelengths of 360-400 nm ３６０－４００ＡＶＥ less than 15% (iii-5) Average internal transmittance T in the spectral transmittance curve at wavelengths of 400-430 nm ４００－４３０ＡＶＥ over 40% (iii-6) Average internal transmittance T in the spectral transmittance curve at wavelengths of 430-500 nm ４３０－５００ＡＶＥ over 90% (iii-7) In the spectral transmittance curve for wavelengths of 350-450 nm, the absolute difference between the wavelength UV10 when the internal transmittance is 10% and the wavelength UV70 when the internal transmittance is 70% is 17 nm or less. (iii-8) Internal transmittance T at a wavelength of 700 nm ７００ less than 5% (iii-9) In the spectral transmittance curve at wavelengths of 600-700 nm, the wavelength IR50, where the internal transmittance is 50%, is at 610-670 nm.

9. The optical filter according to claim 4, wherein the UV dye 2 comprises a merocyanine compound.

10. The optical filter according to claim 1, wherein the IR dye comprises at least one compound selected from squarylium compounds, phthalocyanine compounds, and cyanine compounds.

11. The optical filter according to claim 1, wherein the resin is a transparent resin.

12. The optical filter according to claim 11, wherein the transparent resin includes a polyimide resin.

13. An imaging apparatus comprising an optical filter according to any one of claims 1 to 12.

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